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Propagate section alignment to segment headers
ClosedPublic

Authored by dmikulin on Jul 24 2017, 1:19 PM.

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Summary

If user requested section alignment is greater than MaxPageSize, it's not propagated to segment headers correctly.

This revision was automatically updated to reflect the committed changes.

Path

Size

lld/

ELF/

2 lines

test/

ELF/

linkerscript/

3 lines

Show First 20 Lines • Show All 1,654 Lines • ▼ Show 20 Lines	if (First) {
P.p_filesz += Last->Size;		P.p_filesz += Last->Size;
P.p_memsz = Last->Addr + Last->Size - First->Addr;		P.p_memsz = Last->Addr + Last->Size - First->Addr;
P.p_offset = First->Offset;		P.p_offset = First->Offset;
P.p_vaddr = First->Addr;		P.p_vaddr = First->Addr;
if (!P.HasLMA)		if (!P.HasLMA)
P.p_paddr = First->getLMA();		P.p_paddr = First->getLMA();
}		}
if (P.p_type == PT_LOAD)		if (P.p_type == PT_LOAD)
P.p_align = Config->MaxPageSize;		P.p_align = std::max<uint64_t>(P.p_align, Config->MaxPageSize);
else if (P.p_type == PT_GNU_RELRO) {		else if (P.p_type == PT_GNU_RELRO) {
P.p_align = 1;		P.p_align = 1;
// The glibc dynamic loader rounds the size down, so we need to round up		// The glibc dynamic loader rounds the size down, so we need to round up
// to protect the last page. This is a no-op on FreeBSD which always		// to protect the last page. This is a no-op on FreeBSD which always
// rounds up.		// rounds up.
P.p_memsz = alignTo(P.p_memsz, Target->PageSize);		P.p_memsz = alignTo(P.p_memsz, Target->PageSize);
}		}

▲ Show 20 Lines • Show All 243 Lines • Show Last 20 Lines

	# REQUIRES: x86			# REQUIRES: x86
	# RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %s -o %t.o			# RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %s -o %t.o
	# RUN: echo "SECTIONS { .foo : ALIGN(2M) { *(.foo) } }" > %t.script			# RUN: echo "SECTIONS { .foo : ALIGN(2M) { *(.foo) } }" > %t.script
	# RUN: ld.lld -o %t --script %t.script %t.o -shared			# RUN: ld.lld -o %t --script %t.script %t.o -shared
	# RUN: llvm-readelf -S %t \| FileCheck %s			# RUN: llvm-readelf -S -l %t \| FileCheck %s

	# CHECK: .foo PROGBITS 0000000000200000 200000 000008 00 WA 0 0 2097152			# CHECK: .foo PROGBITS 0000000000200000 200000 000008 00 WA 0 0 2097152
				# CHECK: LOAD 0x200000 0x0000000000200000 0x0000000000200000 {{.*}} RW 0x200000

	.section .foo, "aw"			.section .foo, "aw"
	.quad 42			.quad 42